My faithful (touch wood) 2005 facelift C Class estate has thrown up a problem - COMAND intermittantly doesn't know where it is, which left me in something of a pickle in Windsor the other day! That's the second time it's happened in the last couple of weeks. I know the aerial can fail (I assume it's the external one on the rear door?) but I read that in that case the bottom info bar on the display will show 0 satellites - what happens in mine is that info bar disappears altogether. Anyone experienced this issue before?